Thursday, January 14, 2016

A Rant About Jacklines and Tethers

rev. 7-24-2024

Windward vs. Centerline

The old conventional wisdom was windward and leeward lines, in as far as the cabin and shrouds would allow. Now the new mantra is centerline, and that anything else is unsafe and the user uninformed. They blithely ignore facts suggest something different:

  • You can't slide uphill.
  • Every case of injury by dragging along side was to leeward. They were caught in the bow wave.
  • It is farther to leeward if the jackline is to windward.
  • Waves and gusts come from windward.
The new internet forum wisdom feels more like group think than change based in evidence and experience. By all means move the jacklines in as far as practical, but I believe the physics of falling limit windward overboard incidents. If you know of a documented case, please comment.

[note: The Cal June Jim Buoy model 9225 harness that I am wearing does not pass ISAF or ISO standards and I am not recommending it.It is lightweight, comfortable, and I believe that it is adequate with the shock absorbing tethers that I use. The failures occurred at forces 3 to 4 times greater than my engineering design allows.]
 
7-24-2024. I have long since replaced this with a better harness, but still home-made (I have experience fabricating rock climbing gear--don't try this at home.  The reasons I fabricated my own are:
  • Wider chest band. Testing suggested that anything less than 3 inches is asking for a rib injury.
  • Fleece lining.Much more comfortable if wearing a thin shirt or no shirt.
  • Easier on-off. The new harness closes with a non-load bearing 1.5 inch Fastex buckle. The closure is maintained in use by the tether clip. 
  • Non-adjustable for lightweight and simplicity. One for summer, one for winter, to allow for layers.

Watch in Practical Sailor for an article on jackline locations.

 For me, windward lines and short tethers are the best bet. And my boat doesn't even lean!
 

Quick Release vs. Locking Carabiner at Chest End of Tether

As a single hander, I'm fairly certain that cutting myself free is seldom better.
  • Cold water. Today, for example, I was sailing on the Chesapeake with 34F water temperatures. I did not see a single boat over a 4 hour period. Unless we all take to wearing drysuits, the only ending is slowly freezing in your PFD. 
  • Accidental opening. Ever have a spinnaker shackle release unexpectedly? Granted, it was generally because the shackle was not closed properly, but that is only proof accidents happen. A locking biner is more secure.
  • Offshore. Same as cold water. Yeah, someone could be coming for you. Probably not. 

I don't fancy the idea of dragging, so I keep my tether short when near the rail, and crawl when I need to.

Not a screw-lock on the tether end (Kong Tango). That would be silly. 

rev. 7-24-2024. I now have tethers with snap shackles on the harness end and tethers with a Kong Tango. I feel like the snap shackle makes sense in-shore and if the water is warm or I am wearing a dry suit. Swimming is better than dragging.  But I still feel it is situation specific and that US Sailing is wrong (require snap shackles) and World Sailing is right (leaves the choice to the user). For example, if I were single handing across and ocean , I still don't see how releasing is going to be much better, and I still feel that accidental release is the greater risk.

 

 

As for multihulls, just keep the jacklines well in the from the edge. You've got lots of room. Also, because multihulls can stuff and stop fast, terminated the jacklines 4-5 feet back from the front edge of the tramp.

No comments:

Post a Comment